Activated carbon foams

Product Hterature on KURASHEET activated carbon foam sheets, Kuraray Chemical Co., Ltd., Japan, 1987. 

Table 2 shows the density and IR transmission of pure PS (sample A) and four activated carbon foam samples (samples B-E). With the increase of moisture content, the foam density tends to decrease, which enhances the insulating value. For the IR transmission property, with the addition of activated carbon, its value decreases greatly, which indicates that activated carbon is a good IR absorber. Moisture content shows no effect on the IR transmission property. As described above, IR transmission is a relevant parameter of insidation property. A series of IR transmission measurements of the... 

Table 2. Bulk density and IRtransntission of PS and PS + activated carbon foams...

Color None Decaying organic material and metallic ions causing color may cause foaming in boilers hinders precipitation methods such as iron removal, hot phosphate softening can stain product in process use Coagulation, filtration, chlorination, adsorption by activated carbon... 

Color Boiler foaming Presents problems with iron removal Discoloration of mantifactured produce Adsorption (activated carbon Coagulation Filtration Chlorination... 

Figure 9.2 Fiber and foam structures, (a) Knitted silica fibers catalyst. (Reprinted from [7].) (b) Woven active carbon fiber catalyst. (Reprinted from [8].) (c) Aluminum foam. (Reprinted from [9].)...

Shredding and fractionation of the main unit takes place under partial vacuum in a special shredder. PU foamed with CFCs is pressed out as completely as possible. The vitiated air from the shredder and the press is cleaned through activated carbon and passed through a condensation cooling system. By this means, the foaming agent may be almost entirely recovered. 

An activated carbon (Nuchar RGC Powder, 879-R-02) was supplied by the Chemical Division of Westvaco, Covington, VA. A slurry of the carbon was made in water and emulsified with a TDI-based hydrophilic polyurethane prepolymer (Hypol 2002, Dow Chemical, Midland, MI). Immediately after mixing, the emulsion was grafted to a 30-ppi polyether polyurethane (Crest Foam T-30, Monachie, NJ.). The amount of carbon was determined gravimetrically to be 29% by weight. 

Novel Manufacturing Processes. Different chemical activation processes have been used to produce carbons with enhanced adsorption characteristics. Activated carbons of exceptionally high surface area (>3000 m2/g) have been produced by the chemical activation of carbonaceous materials with potassium hydroxide (28,29). Activated carbons are also produced commercially in the form of cloths (30), fibers (31), and foams (32) generally by chemical activation of the precursor with a Lewis acid such as aluminum chloride, ferric chloride, or zinc chloride. 

Sodium Salt (54)3717a,20 20,21-Bismethylenedioxy-1, 2 -dihydroxypregn-4-ene-3, l-dione (53).37 A solution of 100 g of 17a,20 20,21-bismethylene-dioxypregna-l,4-diene-3,ll-dione (prednisone BMD) (52) in 720 ml of pyridine is cooled to 5° and treated with a solution of 69.9 g of osmium tetroxide in 408 ml of pyridine. The mixture, which turns black within 5 min is allowed to stand at room temperature for five days and then is added with stirring to 13.4 liters of petroleum ether. The crude osmate ester is isolated by filtration and washed with petroleum ether to remove most of the residual pyridine. The crude product is dissolved in 8 liters of dioxane and kept in an ice bath while a slow stream of hydrogen sulfide is bubbled through the reaction mixture. The precipitated osmium sulfide is removed by filtration, and the filtrate is concentrated to dryness in vacuo. The residual foam is dissolved in 2 liters of acetone, decolorized with activated carbon, filtered and concentrated to a volume of 1 liter. Addition of 1 liter of Skellysolve B affords 38 g of diol (53) A OH 236 mfi (e 14,100). 

Reagent impregnated foams can be used as trapping sorbents for the preconcentration of heavy metals.1 These materials can be used in the same way as activated carbons. 

Air (CDDs) Drawing of approximately 325 m3 of air through quartz fiber filter/polyurethane foam Soxhlet extraction with benzene, volume reduction clean-up using silica, alumina, activated carbon volume reduction addition of [13C12]2,3,7,8-TCDD. HRGC/HRMS MID (EPA TO-9) 1-5 pg/m3 68-140 from ultra pure, filtered air EPA1988g... 

Apart from obvious dry cleaning applications, potential applications of C02-based microemulsions include (i) printed circuit board cleaning, (ii) extraction of contaminants from soils, (Hi) cleaning of polymers, foams, aerogels, porous ceramics, and laser optics, (iv) regeneration of activated carbon beds or catalysts, and (v) the separation of dyestuffs from textiles. 

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